A bank manager who stole HK$200,000 (US$25,000) from a client she said then threatened her into stealing a whopping HK$174 million was jailed for 10 years on Wednesday.

Lau Lai, a senior branch operations and services manager at Standard Chartered Bank, claimed Nie Ho-yin made death threats against her after the initial theft in 2008.

Lau said she was under extreme duress when she used forged documents to convince her colleagues to move the staggering amount to Nie’s bank account over the course of five months in 2016.

Appearing in the High Court, Lau pleaded guilty to eight counts of fraud on Wednesday when the court heard that the career banker, who first took Nie on as a client in 1997, had used fake documents and orders to deceive her colleagues into helping her with the scam.

Lau’s claims that Nie had threatened her with the prospect of losing her job, and the safety of her family, were dismissed as a reasonable excuse by Madam Justice Maggie Poon Man-kay.

Poon said Lau had put herself in the predicament in the first place, and slammed her for committing a “blatant breach of trust” involving an amount that sat “way above” the sentencing guideline past cases have established.

“What she has done has brought disrepute not just to the bank, but also to the faith the public placed on the bank, and Hong Kong’s reputation as an international finance centre,” Poon said, before slapping Lau with a lengthy jail term.

Senior public prosecutor Glen Kong told the court that Lau, who had been in the profession for 33 years, was working at the bank’s Tsim Sha Tsui branch at the time of the offence, which began on April 5, 2016.

Kong said Lau’s crime was eventually uncovered when the bank looked into an unrelated complaint lodged by a different client.

The bank used what are known as “suspense accounts” to store funds temporarily, prosecutors said. Lau had ordered four authorised transfers from those accounts to Nie’s personal account between April 5 and August 5 that year.

Lau, for instance, would tell her subordinates the request originated from the manager of another department. She would prepare a fake document to back that claim up.

When her colleagues detected something was wrong, she would tell them the matter had already been under investigation, causing them to put aside their suspicions.

After she was arrested, Lau told police officers that she had been serving Nie since 1997, and admitted to stealing HK$200,000 from her client in 2008.

Although she had repaid the initial amount, defence counsel David Boyton told the court that Nie had been demanding more money as interest, threatening Lau’s job and family if she did not comply.

Poon said that although Lau was subjected to a “certain degree of pressure”, it fell short of amounting to duress.

“That Nie was able to manipulate her was a direct consequence of her fraudulent act, having appropriated HK$200,000 from [Nie’s] account,” the judge added.

She also cast doubt on the amount of money Lau ended up paying, calling it “disproportional”.

She noted Lau was the sole breadwinner from her family as her husband suffered from a long-term illness, but, Poon said, despite ample opportunity, Lau had not turned herself in “until a point of no return”.

Of the HK$174 million, HK$49 million had been transferred back from Nie’s account by Lau, leaving a total of HK$125 million with Nie.

The remaining amount is a subject of another civil lawsuit lodged by the bank against Nie.